/*

* Copyright (c) 2002-2009 Nokia Corporation and/or its subsidiary(-ies).

* All rights reserved.

* This component and the accompanying materials are made available

* under the terms of the License "Eclipse Public License v1.0"

* which accompanies this distribution, and is available

* at the URL "http://www.eclipse.org/legal/epl-v10.html".

*

* Initial Contributors:

* Nokia Corporation - initial contribution.

*

* Contributors:

*

* Description: 

*

*/

#include "tbasicmathsfb.h"

#include "t_input.h"

#include "t_output.h"

#include <bigint.h>

#include <random.h>

CTestAction* CBasicMathsFB::NewL(RFs& aFs, CConsoleBase& aConsole, 

	Output& aOut, const TTestActionSpec& aTestActionSpec)

	{

	CTestAction* self = CBasicMathsFB::NewLC(aFs, aConsole,

		aOut, aTestActionSpec);

	CleanupStack::Pop();

	return self;

	}

CTestAction* CBasicMathsFB::NewLC(RFs& aFs, CConsoleBase& aConsole, 

	Output& aOut, const TTestActionSpec& aTestActionSpec)

	{

	CBasicMathsFB* self = new(ELeave) CBasicMathsFB(aFs, aConsole, aOut);

	CleanupStack::PushL(self);

	self->ConstructL(aTestActionSpec);

	return self;

	}

CBasicMathsFB::~CBasicMathsFB()

	{

	delete iBody;

	}

CBasicMathsFB::CBasicMathsFB(RFs& aFs, CConsoleBase& aConsole, Output& aOut)

	: CTestAction(aConsole, aOut), iFs(aFs)

	{

	}

void CBasicMathsFB::ConstructL(const TTestActionSpec& aTestActionSpec)

	{

	CTestAction::ConstructL(aTestActionSpec);

	iBody = HBufC8::NewL(aTestActionSpec.iActionBody.Length());

	iBody->Des().Copy(aTestActionSpec.iActionBody);

	//HBufC8* length = Input::ParseElementHexL(*iBody, _L8("<bits>"));

	TUint bits = Input::ParseIntElement(*iBody, _L8("<bits>"), _L8("</bits>"));

	// the final /7 gives the number of times we have to increment by 7 to get

	// to that number of bytes and hence bits.

	iIterations = ((bits+7)/8)/7 + 1;

	}

void CBasicMathsFB::DoPerformPrerequisite(TRequestStatus& aStatus)

	{

	TRequestStatus* status = &aStatus;

	User::RequestComplete(status, KErrNone);

	iActionState = CTestAction::EAction;

	}

void CBasicMathsFB::DoPerformPostrequisite(TRequestStatus& aStatus)

	{

	TRequestStatus* status = &aStatus;

	iFinished = ETrue;

	User::RequestComplete(status, KErrNone);

	}

void CBasicMathsFB::DoReportAction(void)

	{

	}

void CBasicMathsFB::DoCheckResult(TInt)

	{

	}

void CBasicMathsFB::PerformAction(TRequestStatus& aStatus)

	{

	__UHEAP_MARK;

	TRequestStatus* status = &aStatus;

	iResult = ETrue;

	//min max values for NewRandomLC call

	RInteger min = RInteger::NewL(10);

	CleanupStack::PushL(min);

	RInteger max = RInteger::NewL(100);

	CleanupStack::PushL(max);

	//Generate iIterations*7 byte random sequences we are using 7 as it's a generator

	//mod 8.  Thus we'll cycle through every value (0-7) every 8 iterations.

	//This gives us a better feeling that certain byte lengths (and thus bit

	//lengths as the byte is chosen randomly) don't have errors.

	for(TUint i=1; i<iIterations; i++)

		{ 

		HBufC8* buf = HBufC8::NewMaxLC(i*7);

		TPtr8 ptr = buf->Des();

		TRandom::RandomL(ptr);

		//This is this iteration's random number

		RInteger initial = RInteger::NewL(ptr);

		CleanupStack::PushL(initial);

		//get a number x | 10 < x < 100

		RInteger crange = RInteger::NewRandomL(min, max);

		CleanupStack::PushL(crange);

		TUint range = crange.ConvertToLongL();

		CleanupStack::PopAndDestroy(); //crange

		AddSub(initial, range);

		MulDiv(initial, range);

		//GCD

		CleanupStack::PopAndDestroy(); //initial

		CleanupStack::PopAndDestroy();//buf

		iConsole.Printf(_L("."));

		}

	//Test a single iteration where the initial random number is less than a

	//word so the division and modulo routines that take words rather than

	//TIntegers can run.

	//do

		{

		//This is this iteration's random number

		RInteger initial = RInteger::NewRandomL(31);

		CleanupStack::PushL(initial);

		//get a number x | 10 < x < 100

		RInteger crange = RInteger::NewRandomL(min, max);

		CleanupStack::PushL(crange);

		TUint range = crange.ConvertToLongL();

		CleanupStack::PopAndDestroy(&crange); //crange

		AddSub(initial, range);

		MulDiv(initial, range);

		CleanupStack::PopAndDestroy(&initial); //initial

		iConsole.Printf(_L("."));

		} //while (0);

	CleanupStack::PopAndDestroy();//max

	CleanupStack::PopAndDestroy(); //min

	User::RequestComplete(status, KErrNone);

	iActionState = CTestAction::EPostrequisite;

	__UHEAP_MARK;

	}

void CBasicMathsFB::AddSub(const TInteger& aInitial, TUint aRange)

	{

	__UHEAP_MARK;

	//This is the copy we are going to do stuff to

	RInteger a = RInteger::NewL(aInitial);

	CleanupStack::PushL(a);

	// compute a*aRange using doubling

	TUint j=1;

	for(; j<aRange; j++)

		{

		a += aInitial;

		}

	//b = a*aRange;

	RInteger b = RInteger::NewL(a);

	CleanupStack::PushL(b);

	//compute (a*aRange)/aRange using subtraction

	for(j=1; j<aRange; j++)

		{

		b -= aInitial;

		}

	// b should be the same as the initial value

	if( b != aInitial )

		{

		iResult = EFalse;

		iOut.writeString(_L("AddSub Failure:"));

		iOut.writeNewLine();

		}

	RInteger c = RInteger::NewL(aInitial);

	CleanupStack::PushL(c);

	// compute a*aRange using normal multiplication

	c *= aRange;

	// c and a should now be the same

	if( c != a )

		{ 

		iResult = EFalse;

		}

	RInteger d = RInteger::NewL(a);

	CleanupStack::PushL(d);

	//compute (a*aRange)/aRange using normal division

	d /= aRange;

	if( d != aInitial )

		{

		iResult = EFalse;

		}

	RInteger e = RInteger::NewL(a);

	CleanupStack::PushL(e);

	e %= aRange;

	// (a*aRange)%aRange == 0

	if( e != 0 )

		{

		iResult = EFalse;

		}

	CleanupStack::PopAndDestroy(5); //e,d,c,b,a

	__UHEAP_MARKEND;

	}

void CBasicMathsFB::MulDiv(const TInteger& aInitial, TUint aRange)

	{

	__UHEAP_MARK;

	//This is the copy we are going to do stuff to

	RInteger a = RInteger::NewL(aInitial);

	CleanupStack::PushL(a);

	//compute a = aInitial^aRange using repeated multiplication

	TUint j=1;

	for(; j<aRange; j++)

		{

		a *= aInitial;

		}

	//b = a

	RInteger b = RInteger::NewL(a);

	CleanupStack::PushL(b);

	//try to find aInitial by repeatedly dividing b by aInitial aRange times

	for(j=1; j<aRange; j++)

		{

		TRAPD(res, b /= aInitial);

		//the first time through aInitial is 0 so this is expected

		if(res == KErrDivideByZero && aInitial.IsZero())

			{

			break;

			}

		else if(res == KErrDivideByZero && aInitial.NotZero())

			{

			iResult = EFalse;

			}

		else if(res != KErrNone)

			{

			User::Leave(res);

			}

		}

	// b should be the same as the initial value

	if( b != aInitial )

		{

		iResult = EFalse;

		}

	//tests division by something smaller than a word

	if(aInitial.WordCount() <= 1)

		{

		RInteger dividend = RInteger::NewL(a);

		CleanupStack::PushL(dividend);

		for(j=1; j<aRange; j++)

			{

			RInteger quotient;

			//try to find aInitial by repeatedly dividing dividend by aInitial aRange times 

			TRAPD(res, quotient = dividend.DividedByL(aInitial.ConvertToLongL()));

			//the first time through aInitial is 0 so this is expected

			if(res == KErrDivideByZero && aInitial.IsZero())

				{

				break;

				}

			else if(res == KErrDivideByZero && aInitial.NotZero())

				{

				iResult = EFalse;

				}

			else if(res != KErrNone)

				{

				User::Leave(res);

				}

			dividend.Set(quotient);

			}

		if( dividend != aInitial )

			{

			iResult = EFalse;

			}

		TUint remainder=1;

		TRAPD(res, remainder = a.ModuloL(aInitial.ConvertToLongL()));

		//the first time through aInitial is 0

		if(res != KErrDivideByZero && res != KErrNone)

			{

			User::Leave(res);

			}

		else if(res == KErrDivideByZero && aInitial.NotZero())

			{

			iResult = EFalse;

			}

		//else we have an expected divide by zero, ignore it.

		if(remainder != 0)

			{

			iResult = EFalse;

			}

		CleanupStack::PopAndDestroy(&dividend);

		}

	RInteger c = RInteger::NewL(aRange);

	CleanupStack::PushL(c);

	RInteger d = aInitial.ExponentiateL(c);

	CleanupStack::PushL(d);

	// c and a should now be the same

	if( d != a )

		{ 

		iResult = EFalse;

		}

	RInteger e = RInteger::NewL(a);

	CleanupStack::PushL(e);

	TRAPD(res, e %= aInitial);

	//the first time through aInitial is 0

	if(res != KErrDivideByZero && res != KErrNone)

		{

		User::Leave(res);

		}

	else if(res == KErrDivideByZero && aInitial.NotZero())

		{

		iResult = EFalse;

		}

	//else we have an expected divide by zero, ignore it.

	// (aInitial^aRange)%aInitial == 0

	if( e != 0 )

		{

		iResult = EFalse;

		}

	CleanupStack::PopAndDestroy(5);//e,d,c,b,a

	__UHEAP_MARKEND;

	}